#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
int main() {
    double sum = 0.0;
    for (int i = 1; i <= 100; i++) {
        if (i % 2 == 1) {
            sum += 1.0 / i;
        }
        else {
            sum -= 1.0 / i;
        }
    }
    printf("The sum is: %f\n", sum);
    return 0;
}
